Research from the University of Illinois is helping to determine the quality of protein in wheat middlings and red dog, two coproducts of the wheat milling process that can be included in diets fed to pigs and other livestock.

Red dog consists mainly of the aleurone layer that lies between the bran and the endosperm, along with small particles of bran, germ, and flour. Wheat middlings are granular particles of the wheat endosperm, bran, and germ. They contain about three times as much dietary fiber as red dog.

"We have information about the digestibility of crude protein in some wheat coproducts produced in Canada and China, but only very limited information about the nutritional value of wheat middlings and red dog produced in the United States," says Hans H. Stein, professor in the Department of Animal Sciences at U of I.

"In addition, because wheat coproducts vary in terms of the conditions under which they are produced, their nutritional value may vary as well," he says.